Reaction Time Test
Wait for green. Click as fast as you can. Five rounds, your average and best time — with an honest note about what your device adds to the number.
Your reaction time
Honesty note: this number includes your display and input latency (typically 20–60 ms), so it flatters nobody and wrongs nobody equally. Compare only against yourself, on the same device.
What this test measures
This is a simple reaction time task: one stimulus (the screen turns green), one response (click). It measures the speed of your visual-motor loop — eye to brain to hand — which is the most basic building block of processing speed. It is deliberately not a "choice" reaction task and not an intelligence test: it tells you how fast your wiring responds today, nothing more grandiose.
What's average — and what moves it
Large online datasets converge on a median around 273 ms for this task, with the bulk of people between 200 and 350 ms. The reliable movers: age (simple RT is fastest in the early-to-mid 20s and slows a few milliseconds per decade), sleep (deprivation adds tens of milliseconds), alertness and caffeine (small, real effects), and — bigger than people expect — your hardware: a 60 Hz office monitor plus a laptop trackpad can add 50 ms that a 144 Hz display and gaming mouse don't.
Reaction speed correlates with measured intelligence only weakly (r ≈ 0.2–0.3 in the literature) — a fun fact, not a diagnosis. If you want the actual cognitive estimate, the 35-puzzle matrix test is the tool; this page is the warm-up lap.
Reaction time — common questions
What is a good reaction time?
For a simple visual task like this, large online datasets put the median around 273 milliseconds, with most people landing between 200 and 350 ms. Under 250 ms is genuinely fast; under 200 ms on a standard setup is exceptional (competitive gamers and athletes live there). Remember that your device adds latency — see the honesty note below the test.
Why is my reaction time different on my phone vs my computer?
Because you are measuring the whole chain: display refresh, input hardware and browser processing all add 20–60 ms that have nothing to do with your nervous system. Touchscreens typically register taps slower than a gaming mouse clicks. Compare scores only on the same device, and treat cross-device differences as hardware trivia.
Does reaction time relate to IQ?
Weakly but genuinely: simple reaction time correlates with measured intelligence at roughly r ≈ 0.2–0.3 in the research literature — enough to be scientifically interesting, far too little to infer anything about an individual. A fast click says your visual-motor loop is quick today; it is not a cognitive assessment. For that, take the matrix test.
Can I improve my reaction time?
A little, and it plateaus fast. Practice on a specific task trims maybe 10–30 ms before you hit your physiological floor. The bigger levers are boring: sleep (deprivation adds tens of milliseconds), alertness and caffeine (a real but small effect), and age (simple RT slows gradually from the mid-20s — a few milliseconds per decade).
Why five rounds?
Single reactions are noisy — attention drifts, you anticipate, you blink. Averaging five valid rounds (false starts excluded) gives a much more stable estimate, and we show your best round separately for bragging rights.